The viewpoint-specific failure of modern 3D displays in laparoscopic surgery.

PURPOSE: Surgeons conventionally assume the optimal viewing position during 3D laparoscopic surgery and may not be aware of the potential hazards to team members positioned across different suboptimal viewing positions. The first aim of this study was to map the viewing positions within a standard operating theatre where individuals may experience visual ghosting (i.e. double vision images) from crosstalk. The second aim was to characterize the standard viewing positions adopted by instrument nurses and surgical assistants during laparoscopic pelvic surgery and report the associated levels of visual ghosting and discomfort. METHODS: In experiment 1, 15 participants viewed a laparoscopic 3D display from 176 different viewing positions around the screen. In experiment 2, 12 participants (randomly assigned to four clinically relevant viewing positions) viewed laparoscopic suturing in a simulation laboratory. In both experiments, we measured the intensity of visual ghosting. In experiment 2, participants also completed the Simulator Sickness Questionnaire. RESULTS: We mapped locations within the dimensions of a standard operating theatre at which visual ghosting may result during 3D laparoscopy. Head height relative to the bottom of the image and large horizontal eccentricities away from the surface normal were important contributors to high levels of visual ghosting. Conventional viewing positions adopted by instrument nurses yielded high levels of visual ghosting and severe discomfort. CONCLUSIONS: The conventional viewing positions adopted by surgical team members during laparoscopic pelvic operations are suboptimal for viewing 3D laparoscopic displays, and even short periods of viewing can yield high levels of discomfort.

[Simulator sickness and its measurement with Simulator Sickness Questionnaire (SSQ)]. / Zjawisko choroby symulatorowej oraz jej pomiar na przykladzie kwestionariusza do badania choroby symulatorowej - SSQ.

One of the most common methods for studying the simulator sickness issue is the Simulator Sickness Questionnaire (SSQ) (Kennedy et al., 1993). Despite the undoubted popularity of the SSQ, this questionnaire has not as yet been standardized and translated, which could allow us to use it in Poland for research purposes. The aim of our article is to introduce the SSQ to Polish readers, both researchers and practitioners. In the first part of this paper, the studies using the SSQ are discussed, whereas the second part consists of the description of the SSQ test procedure and the calculation method of sample results. Med Pr 2016;67(4):545-555.

A comparison of techniques to mitigate Simulator Adaptation Syndrome.

We investigated the effectiveness of galvanic cutaneous stimulation (GCS) and auditory stimulation in mitigating simulator adaptation syndrome (SAS). Fifteen drivers (9 men; M age = 23.2 years) participated in a driving simulation experiment comparing three different stimulation conditions (GCS, auditory stimulation and no stimulation as a base line condition) in curves on a virtual urban circuit. GCS and auditory stimulation decreased SAS by reducing head sway. Both sources of stimulation can be recommended as countermeasures against SAS. We encourage the use of stimuli which influence the balancing ability to the design of future simulator protocols and devices to mitigate SAS. PRACTITIONER SUMMARY: We have provided evidence on the effectiveness of two different stimuli as countermeasures against simulator adaptation syndrome (SAS). We concluded that the positive impact of body sway might play a role in SAS and therefore encourage the use of stimuli which influence the balancing ability to mitigate the symptoms of SAS.

Cybersickness. A systematic literature review of adverse effects related to virtual reality.

BACKGROUND: Virtual Reality (VR) uses computer technology to create a simulated environment. VR is a growing technology with promising extensive applications in different areas such as Medicine, entertainment, sports, gaming, and simulation. However, information about VR side effects is still limited. We aimed to identify the most frequent physical side effects caused by VR therapeutic applications. METHODOLOGY: All available full-text articles evaluating VR as a therapeutic intervention and side effects using the Simulator Sickness Questionnaire (SSQ) between 2016 and 2021 were consulted across 4 electronic (Entrez Pubmed, Scopus, Science Direct, and Wiley databases). The methodological quality was assessed using the PEDro scale. RESULTS: Ten out of 55 reviewed articles (18%) met inclusion/exclusion criteria, including a sample of 416 patients, mean age of 24.54 (15-52.6)years old. According to the PEDro scale, two articles (20%) were considered good or excellent. Side effects were reported more frequently with head-mounted displays compared to desktop systems, especially disorientation, followed by nausea and oculomotor disturbances. CONCLUSIONS: Although VR might have positive effects as a therapeutic tool, VR can also cause side events. As in any other therapeutic intervention, it is important to understand the effectiveness and safety before planning a VR intervention using a well-designed scientific methodology.

Determining Work-Rest Schedules for Visual Tasks That Use Optical Head-Mounted Displays Based on Visual Fatigue and Visually Induced Motion Sickness Recovery.

This study aimed to determine work-rest schedules for visual tasks of different lengths by evaluating visual fatigue and visually induced motion sickness (VIMS) using an optical head-mounted display (OHMD). Thirty participants were recruited to perform 15 and 30 min visual tasks using an OHMD. After completing each visual task, participants executed six levels of rest time. Critical flicker fusion frequency (CFF) values, relative electroencephalography indices, and Simulator Sickness Questionnaire (SSQ) scores were collected and analyzed. Results indicated that after completing the 15 and 30 min visual tasks, participants experienced visual fatigue and VIMS. There was no significant difference between baseline CFF values, four electroencephalography relative power index values, and SSQ scores when participants completed a 15 min visual task followed by a 20 min rest and a 30 min visual task followed by a 30 min rest. Based on our results, a 20 min rest for visual fatigue and VIMS recovery after a 15 min visual task on an OHMD and a 25 min rest for visual fatigue and VIMS recovery after a 30 min visual task on an OHMD are recommended. This study suggests a work-rest schedule for OHMDs that can be used as a reference for OHMD user guidelines to reduce visual fatigue and visually induced motion sickness.

Postural Control and Psychophysical State Following of Flight Simulator Session in Novice Pilots.

Flight simulators can cause side effects usually called simulator sickness. Scientific research proves that postural instability can be an indicator of the occurrence of simulator sickness symptoms. This study aims to assess changes of postural control and psychophysical state in novice pilots following 2-h exposure to simulator conditions. The postural sway was quantified based on variables describing the displacement of the Center of Pressure (COP) generated in a quiet stance with eyes open (EO) and closed (EC). The psychophysical state was assessed using the Simulator Sickness Questionnaire (SSQ). The research was carried out in a group of 24 novice pilots who performed procedural and emergency flight exercises in the simulator at Instrument Meteorological Conditions. Each subject was examined twice: immediately before the simulator session (pre-exposure test), and just after the session (post-exposure test). The differences in postural stability between pre- and post-exposure to simulator conditions were assessed based on the normalized Romberg quotients, calculated for individual variables. The lower median values of all Romberg quotients confirmed the decreasing difference between the measures with eyes open and with eyes closed in the post-exposure tests. After the flight simulator session in both measurements (EO and EC) the values of the length of sway path (SP), the mean amplitude (MA), the sway area (SA) have changed. The visual contribution to postural sway control was reduced. The median values for all SSQ scores (total, nausea, oculomotor, and disorientation scales) were significantly higher in post-exposure tests. The largest increase was noted in the oculomotor SSQ scores (from 7.6 ± 7.6 to 37.9 ± 26.5). Over 50% of pilots participating in this study expressed symptoms typical of simulator sickness connected with visual induction: fatigue, eyestrain, difficulty focusing and difficulty concentrating. The severity of oculomotor and disorientation symptoms were rated as moderate (total SSQ score of more than 25 and <60). This study concludes that changes noted in the postural control and psychophysical state of the studied pilots after exposure to the flight simulator confirm the occurrence of the simulator sickness symptoms. Although, we did not find significant correlation of postural stability with SSQ scores.

A New Approach for Reducing Virtual Reality Sickness in Real Time: Design and Validation Study.

BACKGROUND: Recently, technology that provides virtual reality (VR) content based on streaming services has been rapidly developed. However, there have been few studies to reduce VR sickness that occurs while the user watches VR content while wearing a head-mounted display (HMD) in real time. OBJECTIVE: Based on this background, we propose a new approach to measure and reduce VR sickness that occurs while the user watches VR content while wearing an HMD in real time. METHODS: The proposed approach is to apply VR sickness reduction methods in accordance with the user's real-time VR sickness level. Three methods that are known to be effective in reducing VR sickness and a single type of VR content were used to examine the effectiveness of the proposed approach, which was confirmed by the experimental results. RESULTS: Our results show that VR sickness significantly decreased when a new approach was applied to VR content (in all cases, P<.05). CONCLUSIONS: From our results, it was confirmed that VR sickness could be measured without wearing additional equipment, and its reduction method could be applied in real time in accordance with the user's condition by the proposed approach in this paper.

Arguing in Favor of Revising the Simulator Sickness Questionnaire Factor Structure When Assessing Side Effects Induced by Immersions in Virtual Reality.

Two issues are increasingly of interest in the scientific literature regarding unwanted virtual reality (VR) induced side effects: (1) whether the latent structure of the Simulator Sickness Questionnaire (SSQ) is comprised of two or three factors, and (2) if the SSQ measures symptoms of anxiety that can be misattributed to unwanted negative side effects induced by immersions in VR. Study 1 was conducted with a sample of 876 participants. A confirmatory factor analysis clearly supported a two-factor model composed of nausea and oculomotor symptoms instead of the 3-factor structure observed in simulators. To tease-out symptoms of anxiety from unwanted negative side effects induced by immersions in VR, Study 2 was conducted with 88 participants who were administered the Trier Stress Social Test in groups without being immersed in VR. A Spearman correlation showed that 11 out of 16 side effects correlated significantly with anxiety. A factor analysis revealed that items measuring general discomfort, difficulty concentrating, sweating, nausea, and vertigo loaded significantly on the anxiety factor comprised of items from the State-Trait Anxiety Inventory. Finally, a multiple regression indicated that the items measuring general discomfort and difficulty concentrating significantly predicted increases in anxiety. The overall results support the notion that side effects associated with immersions in VR consist mostly of a nausea and an oculomotor latent structure and that a few items are confounding anxiety and cybersickness. The data support the suggestion to revise the scoring procedures of the Simulator Sickness Questionnaire when using this instrument with immersions in VR.

[Simulator sickness and the Simulator Sickness Questionnaire in Polish practice. A study involving professional drivers subject to compulsory initial and periodic qualification courses]. / Choroba symulatorowa i Simulator Sickness Questionnaire w polskiej praktyce. Badania kierowców zawodowych podlegajacych obowiazkowym kursom kwalifikacji wstepnej i okresowej.

BACKGROUND: A phenomenon of simulator sickness is measurable in terms of physiological symptoms. The article presents the practical use of the Simulator Sickness Questionnaire (SSQ) in post-exposure research, together with feedback given by the examined drivers. MATERIAL AND METHODS: The study was conducted on the AutoSim AS 1600 simulator, and involved 130 drivers attending preliminary and periodic qualification courses in road transportation. The following tools were used throughout the research: the SSQ by Kennedy et al., translated into Polish by Biernacki et al. (with symptoms including nausea, oculomotor disturbances & disorientation symptoms, and the SSQ total), and a tool evaluating the SSQ (comprehensibility and time consumption on a 1-6 scale). RESULTS: In the study group (N = 130), some statistically significant differences in the SSQ results were observed. Among younger drivers (<29.5 years old) an increased intensity of the simulator sickness symptoms after simulation was recorded (nausea and the SSQ total), and among older drivers (>29.5 years old) - the disorientation symptoms after simulation. The length of sleep and the quality assessment of the conducted task were higher in the asymptomatic groups. Also, the results indicate a positive reception of the tool by the examined individuals (N = 113), with time consumption marked as low (M = 2.44 on a 1-6 scale) and comprehensibility as high (M = 5.62 on a 1-6 scale). CONCLUSIONS: The research indicates the occurrence of simulator sickness symptoms even in simulators, which accurately reflect vehicle movements. The feedback given by the examined individuals, together with the level of involvement in the SSQ use, indicates a positive reception of the tool. Med Pr. 2020;71(1):47-58.

Psychometric evaluation of Simulator Sickness Questionnaire and its variants as a measure of cybersickness in consumer virtual environments.

Cybersickness, i.e. visually induced motion sickness, remains as a negative effect that is detrimental to the user experience of VEs (virtual environments) developed for VR (virtual reality) consumers. As the VR technology evolves, it is rather triggered by application aspects rather than hardware limitations. For this reason, there is still a need for a measurement method to assess and compare VEs for cybersickness effects. SSQ (Simulation Sickness Questionnaire) is used for measuring users' level of sickness symptoms and is highly appreciated in VR research. However, it is criticized for its psychometric qualities and applicability in VR, as a measure of cybersickness. Recently, two variants of SSQ were offered for measuring cybersickness, CSQ (Cybersickness Questionnaire) and VRSQ (Virtual Reality Sickness Questionnaire). There is also another variant with a different factor structure, which we call FSSQ, that is based on French translation of SSQ. Our study compares SSQ and these variants for their psychometric qualities; construct validity, discriminant validity, internal reliability, test-retest reliability and sensitivity to distinguish application aspects of VEs that are related to cybersickness. Using a within-subjects experiment design, we evaluated 7 different VEs with 32 participants through 9 sessions, resulting with 288 responses to the 16-item SSQ. Results suggested that both VRSQ and CSQ were valid and reliable measures of cybersickness, as well as being sensitive to application aspects such as translational and rotational movements required by users for navigation in VEs. Compared to SSQ and FSSQ; the cybersickness questionnaires, CSQ and VRSQ, revealed better indicators of validity. On the other hand, we assume that the development of the two cybersickness scales had limitations in sample size to represent VR consumers and limitations in stimuli to represent the applications aspects of consumer VEs. We suggest further evaluation of cybersickness symptoms with larger samples and broader range of applications to identify the symptoms and the construct of a subjective measurement tool.

[Simulator sickness in the aircraft training of military and civil pilots of various types of aircraft]. / Choroba symulatorowa w szkoleniu pilotów wojskowych i cywilnych róznych typów statków powietrznych.

BACKGROUND: With the rise in popularity and availability of simulators for the aircraft training of pilots, numerous side effects of that technology have been noted among their users. The symptoms of simulator sickness are similar to the symptoms of motion sickness. Dizziness, nausea, as well as spatial disorientation and a limited capacity for concentration may be observed. However, those symptoms depend on individual user's predispositions. MATERIAL AND METHODS: The aim of the research was to assess the probability of occurrence of simulator sickness during exercises in virtual reality, and its impact on the effectiveness of training. Thirty two military and 16 civilian pilots of various types of aircraft took part in the research. For the subjective assessment of the psychophysical condition of the pilots, a questionnaire based on Simulator Sickness Questionnaire (SSQ) was used. RESULTS: Four main factors that are associated with the prevalence of simulator sickness have been identified, i.e., age, a variety of missions, a type of aircraft and susceptibility to motion sickness. CONCLUSIONS: Due to the individual characteristics of each person, determining the risk of occurrence of simulator sickness seems to be difficult. However, there are some factors that increase the probability of getting sick, including cold, medications, lack of sleep and general fatigue. The lack of knowledge about simulator sickness among aircraft pilots appears rather alarming. When access to virtual reality is so wide, the possible ways of expanding the knowledge in this area should be considered, especially in order to obtain better results in simulator sessions. Med Pr. 2019;70(3):317-25.

Virtual reality sickness questionnaire (VRSQ): Motion sickness measurement index in a virtual reality environment.

This study aims to develop a motion sickness measurement index in a virtual reality (VR) environment. The VR market is in an early stage of market formation and technological development, and thus, research on the side effects of VR devices such as simulator motion sickness is lacking. In this study, we used the simulator sickness questionnaire (SSQ), which has been traditionally used for simulator motion sickness measurement. To measure the motion sickness in a VR environment, 24 users performed target selection tasks using a VR device. The SSQ was administered immediately after each task, and the order of work was determined using the Latin square design. The existing SSQ was revised to develop a VR sickness questionnaire, which is used as the measurement index in a VR environment. In addition, the target selection method and button size were found to be significant factors that affect motion sickness in a VR environment. The results of this study are expected to be used for measuring and designing simulator sickness using VR devices in future studies.

Alleviating simulator sickness with galvanic cutaneous stimulation.

OBJECTIVE: In a driving simulation, we investigated the efficacy of galvanic cutaneous stimulation (GCS) provided during curves or intermittently during the whole circuit to mitigate simulator syndrome (SS). BACKGROUND: The literature on how GCS decreases SS, although scarce, has demonstrated the effectiveness of this technique. Stimulation with this and similar techniques has usually been provided in curves or continuously during the whole circuit but never intermittently. This stimulation method could generate a continued activation of processes related to GCS mitigating SS. METHOD: Fifteen drivers (8 men; mean age = 25.5 years) participated in this experiment. We compared the total scores of the Simulator Sickness Questionnaire (SSQ) across three stimulation conditions: (a) curve GCS condition, whereby GCS was provided in curves; (b) intermittent GCS condition, whereby GCS was provided intermittently during the whole circuit; and (c) no-stimulation condition, whereby no stimulation was provided (baseline condition). RESULTS: The experimental outcomes revealed that GCS decreased SS in both the curve and intermittent stimulation conditions. CONCLUSION: We provide evidence that GCS is an effective countermeasure to decrease SS. It could be applied indifferently in curves or intermittently during the whole circuit. APPLICATION: For future interventions, we recommend the use of GCS to mitigate SS with similar intermittent stimulation programs. These programs have a crucial advantage as they are easily integrated into the simulator setup without the necessity of generating a complicated experimental design to stimulate during the curves.